Foam rubber mattress



y 1958 R. ROBBINS FOAM RUBBER MATTRESS Filed May 7, 1954 INVENTOR Ralph Robbins BY W ORNEYS ATT United States Patent p FOAM RUBBER MATTRESS Ralph Robbins, Jamaica, N. Y. Application May 7, 1954, Serial No. 428,164 2 Claims. (Cl. 5-351) This invention relates to a latex foam rubber mattress which is capable of being folded through 180 for use in folding beds and sofas convertible into beds.

When conventional inner spring mattresses are manufactured for use in folding beds and sofas convertible into beds, the spring unit in the mattress must be extremely soft in order to permit the bend or fold through 180". As a result of the soft type of spring unit used, the sleeping surface is unsatisfactory and much too soft by current orthopedic standards. Often the coil springs at the hinge point break away, are distorted and otherwise forced out of position.

With the advent of the large scale use of latex foam rubber in mattresses, many of the manufacturers attempt to substitute foam rubber mattresses for inner spring mattresses. However, the manufacturers found that when a standard foam rubber mattress is folded through one hundred and eighty degrees, the mattress core suffers a great strain exerted on the under side, and after he quent folding or remaining in folded position for a considerable length of time, a crease or a corrugation at the line of fold was set in the top surface of the mattress and formed a bump which could be felt over the mattress surface and which could not be eliminated. As a result, foam rubber mattresses were not generally used as folding mattresses. Thus all the advantages of a foam rubber were not available for folding mattresses, which hitherto have been made of other types of material, and the sections of which are joined together by the ticking or the covering material containing the mattress core.

One object of my invention is to provide a latex foam rubber mattress which permits folding of the rubber without requiring an envelope or covering, and without undue strain on the mattress and which can be folded without permanent distortion of the top surface portion of the mattress and without tearing or otherwise ruining the mattress.

Another object is to provide a foldable mattress which has, when extended, full and uniform compression support throughout the top surface thereof, and affords a complete unbroken one-piece surface for its entire length, uninterrupted by seams, stitches, or additional reinforcement cloth on the top surface of the mattress.

Still another object of this invention is to provide a relatively inexpensive, one-piece, foldable, foam rubber mattress.

Other objects and advantages will be readily apparent from the following detailed description and drawings in which like numerals relate to like parts and in which:

Figure l is a top plan view of a mattress made in accordance with my invention showing the unbroken, one piece top surface;

Fig. 2 is an enlarged cross-sectional view taken along line 2-2 of Fig. 1 showing the hinge groove and reinforcement construction of my mattress; and

Fig. 3 is an enlarged cross-sectional view taken along line 3-3 of Fig. 1 further showing the hinge groove of my mattress.

, 2,835,906 Patented May 27, 1958 A plan view of a foam rubber mattress 1 made in ac cordance with my invention is shown in Fig. 1. The mattress is rectangular in shape and the top surface 2 is unbroken. The width 12 is measured along the shorter side, the length 13 along the longer side, and dotted lines 5 indicate the sides of a hinge groove on which the mattress is folded. The mattress is preferably made of latex foam rubber, .either natural rubber or synthetic rubber or mixtures of the two. It can also be made of a closed cell construction out of rubber or other suitable rubberlike material with a cellular composition. Dotted circles 3 indicate a multiplicity of cores formed in the bottom surface of the mattress to provide springlike action.

Figs. 2 and 3 are cross-sectional views of the mattress and show its basic construction which comprises a multiplicity of core portions or hollows 3 formed in the underside 4 of the mattress and continuous portions 6 which support and sustain the mattress. Intermediate the ends of the mattress and substantially parallel thereto a longitudinal section of one of the continuous portions 6 is subdivided by a cut 7 extending substantially across the width of the mattress and substantially parallel to width 12 as shown by the dotted lines in Fig. l.

Molded integral with the mattress and along both sides of the surface of the cut 7 is a reinforcement 8, made of a longitudinal strip of cloth or other suitable reinforcement material such as Fiberglas mesh or mat, which is folded back upon itself along a centraly located folding line. Also molded into the mattress is on the top surface 2, approximately above the cut 7, an additional reinforcement 9. The reinforcement 9 may be continuous or intermittent around the mattress as necessary.

As shown in Fig. 3, the cut 7 preferably does not extend across the full width of the mattress, and supporting portions 11 are located along both sides of the groove so that it cannot be seen from the top or either side. If desired, the cut 7 can extend into the sides or supporting portions 11 of the mattress. Under any circumstances, it should not be more than two inches and preferably one inch in from the side of the mattress. As shown in Fig. 2, the cut 7 should extend to within an inch or less of the top surface to provide a narrow hinge portion 14 of the mattress about which the two mattress sections bend or hinge.

The reinforcements 8 and 9 can be positioned by being located in the mold (not shown) prior to filling the mold with foamed latex.

This invention is equally suitable for solid mattress of foam rubber construction or mattress with different core structures from that shown.

Having thus described my invention, what I claim is:

1. A rectangular shaped sponge rubber mattress having unbroken top and side surfaces and a multiplicity of core holes in its bottom surface, means including an incision having a width that is a small fraction of an inch extending substantially across the width of the mattress in the middle portion thereof and terminating within about two inches from each of said side surfaces providing a hinge portion for the mattress so that the top surfaces of the mattress can be readily folded against one another through degrees, and means for reinforcing said hinge portion comprising a pair of narrow woven strips molded integral with the mattress, one of said strips extending substantially the full length of said groove and having its opposite side edges at the marginal edges of said groove and the other of said strips being integrally joined to the mattress on opposite sides of said groove and having end edges adjacent the top marginal side edges of said mattress.

2. A foam rubber mattress comprising a rectangular sponge rubber piece having unbroken top and side sur- 3 faces and a multiplicity of core holes extended thereinto from its lower surface and being subdivided into two sections by means of an incision extending substantially across the width of the sponge rubber piece in the middle portion thereof and terminating within about two inches from each of said top and side surfaces to provide a hinge portion for the sponge rubber piece so that the top surfaces of sections thereof at both sides of said incision can be folded against one another through onerhundred and eighty degrees, a first reinforcement strip having two longitudinal portions folded back upon themselves along a longitudinal folding line and being secured to those sections of said sponge rubber piece which are adjacent said incisions so as to reinforce the same from below, and

a second reinforcement strip secured to a section of the References Cited in the file of this patent UNITED STATES PATENTS Re. 19,355 Gursky et a1. Oct. 30, 1934 1,549,289 Bradley Aug. 11, 1925 2,192,601 Mattison Mar. 5, 1940 2,271,058 Binns Jan. 27, 1942 2,589,579 Slayen Mar. 18, 1952 2,626,407 Kurry Jan. 27, 1953 2,779,031 Arpin Jan. 29, 1957 

